In Patent Document 1, there is shown an arrangement in which, for cooling an electric motor as a drive source of a gas compression mechanical section by using a flow of sucked refrigerant in a housing, the electric motor is installed in a suction chamber that is communicated with a suction port of the housing.
When the gas compression mechanism section is driven by the electric motor, the refrigerant is sucked from the suction port of the housing to the gas compression mechanism section through the suction chamber and the refrigerant thus compressed by the gas compression mechanism section is discharged to the outside from a discharge port provided by the housing.
Although the refrigerant sucked into the housing contains a lubricating oil for lubricating the gas compression mechanical section, part of the lubricating oil is separated from the refrigerant in the suction chamber and thus it sometimes occurs that the separated lubricating oil is collected in the bottom portion of the suction chamber.
If the amount of the separated lubricating oil collected and stagnated in the bottom portion of the suction chamber is increased, the amount of lubricating oil fed to the gas compression mechanism section is reduced, which induces a difficulty in obtaining a smoothed operation of the gas compression mechanism section.
In view of the above, Patent Document 1 proposes an arrangement which comprises a refrigerant guide path that guides the refrigerant sucked to the suction chamber to the gas compression mechanism section and a lubricating oil guide path that has one end opened to the bottom portion of the suction chamber and the other end opened to the refrigerant guide path, wherein due to the flow of the refrigerant in the refrigerant guide path, the lubricating oil collected in the bottom portion of the suction chamber is moved or brought to the gas compression mechanism section through the lubricating oil guide path.
With the above-mentioned arrangement, undesired liquid compression at the time of restarting the gas compression mechanism is avoided and collection and stagnation of the lubricating oil in the suction chamber is also avoided.